I suggested to use adaptive modulation and coding techniques on SDR platform.
If possible adopt offline signal processing in simulation (Matlab/Simulink or LabVIEW) environments. We can easily control SDR devices through Matlab/Simulink or LabVIEW.
Good day, I've somewhat interested in the question, May you briefly clarify the type of modulator, what do you adjust and what is a goal and potential result of adjusting?
Adaptive modulation and coding are specified for LTE mobile communication system and for WIMAX This is utilized to maximize the spectral efficiency of the wireless fading channel and overcome frequency selective fading and fast fading due to Doppler effect.. Channel coding as block codes and convolutional codes are utilized for error detection and correction. The code rate is adjusted for the required error correcting capability of the code. Turbo coding is one of the most efficient channel coding and it has a powerful correcting capability. The adaptive modulation is QAM modulation with the order from 4 to 64 and higher according to signal to noise ratio of the channel. For wide band communication systems OFDM multi carrier modulation is used to mitigate the inter-symbol interference.
Nearly all advanced communication systems contains such building blocks. You can find matlab models and Simulink models for the building blocks and for the whole systems. If you visited my page on the researchgate you will find some papers treating this issue in detail. If you are interested please visit the link:https://www.researchgate.net/profile/Abdelhalim_Zekry/publications